THE CELL DOCTRINE. 47 



to one central or capital cell, around which they are 

 grouped. It would appear that from this central cell, 

 all the other cells of its department derive their 

 origin. It is the mother of all those within its own 

 territory. It has absorbed materials of nourishment 

 for them while in a state of development, and has 

 either passed them off after they have been fully 

 formed, or have arrived at a stage of growth when 

 they can be developed by their own powers. 



" Centres of nutrition are of two kinds, those 

 which are peculiar to the textures, and those which 

 belong to the organs. The nutritive centres of the 

 textures are in general permanent. Those of the 

 organs are in most instances peculiar to their em- 

 bryonic stage, and either disappear ultimately or 

 break up into the various centres of the textures of 

 which the organs are composed. 



" A nutritive centre, anatomically considered, is merely 

 a cell, the nucleus of which is the permanent source of suc- 

 cessive broods of young cells, which from time to time 

 fill the cavity of their parent, pass off in certain 

 directions, and under various forms, according to 

 the texture or organ of which their parent forms a 

 part." 



Prof. Goodsir does not fail to state in the first para- 

 graph of his paper, that with many of these centres 

 anatomists have been for some time familiar, but 

 further remarks that with few exceptions they have 

 looked upon them as embryonic structures. He 

 alludes in a note to the observations of Bowman 

 and Barry, the former on "Muscle," and the latter 

 " On the Corpuscles of the Blood," in Philosophical 



